From 9632a3299bb1897f01c6a485ff035b20e61d7ae1 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 21 Apr 2019 21:41:45 +0200 Subject: [PATCH] RAS/CEC: Sanity-check array on every insertion Check the elements order in the array after every insertion. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac --- drivers/ras/cec.c | 37 +++++++++++++++++++++++++++++++------ 1 file changed, 31 insertions(+), 6 deletions(-) diff --git a/drivers/ras/cec.c b/drivers/ras/cec.c index f57e869dfea2..da5797c38051 100644 --- a/drivers/ras/cec.c +++ b/drivers/ras/cec.c @@ -276,11 +276,39 @@ static u64 __maybe_unused del_lru_elem(void) return pfn; } +static bool sanity_check(struct ce_array *ca) +{ + bool ret = false; + u64 prev = 0; + int i; + + for (i = 0; i < ca->n; i++) { + u64 this = PFN(ca->array[i]); + + if (WARN(prev > this, "prev: 0x%016llx <-> this: 0x%016llx\n", prev, this)) + ret = true; + + prev = this; + } + + if (!ret) + return ret; + + pr_info("Sanity check dump:\n{ n: %d\n", ca->n); + for (i = 0; i < ca->n; i++) { + u64 this = PFN(ca->array[i]); + + pr_info(" %03d: [%016llx|%03llx]\n", i, this, FULL_COUNT(ca->array[i])); + } + pr_info("}\n"); + + return ret; +} int cec_add_elem(u64 pfn) { struct ce_array *ca = &ce_arr; - unsigned int to; + unsigned int to = 0; int count, ret = 0; /* @@ -345,6 +373,8 @@ int cec_add_elem(u64 pfn) if (ca->decay_count >= CLEAN_ELEMS) do_spring_cleaning(ca); + WARN_ON_ONCE(sanity_check(ca)); + unlock: mutex_unlock(&ce_mutex); @@ -402,7 +432,6 @@ DEFINE_DEBUGFS_ATTRIBUTE(count_threshold_ops, u64_get, count_threshold_set, "%ll static int array_dump(struct seq_file *m, void *v) { struct ce_array *ca = &ce_arr; - u64 prev = 0; int i; mutex_lock(&ce_mutex); @@ -412,10 +441,6 @@ static int array_dump(struct seq_file *m, void *v) u64 this = PFN(ca->array[i]); seq_printf(m, " %03d: [%016llx|%03llx]\n", i, this, FULL_COUNT(ca->array[i])); - - WARN_ON(prev > this); - - prev = this; } seq_printf(m, "}\n");